Above-ground pipelines are well known for transporting fluid materials of various types from a first location to a second one. Tank farms for transporting oil or even wine are well known uses for above-ground pipelines. Butterfly valves of various types are ubiquitous and positioned in-line in a pipeline to regulate the flow of fluid materials. The mechanical opening and closing of the butterfly valves causes wear on valve seals and metal parts, necessitating that the butterfly valves present in above-ground pipelines have their components serviced or replaced at regular intervals, usually every 180 days in the case of tank farm facilities which experience industrial-level use.
In the past, servicing or replacement of in-line butterfly valves or their components required that the pipeline be disassembled. To do so meant that the valve be unbolted from the flanges of adjacent pipe sections, which required the pipe sections to be supported by jacks to keep the adjacent pipe sections from sagging while the in-line valve is replaced and bolted up to the flanges of the adjacent pipe sections.
Removable in-line valves which allow partial removal and replacement of parts have been in existence for quite some time, reference U.S. Pat. No. 3,752,181, issued to Morris et al. However, the problem of removing the valve from adjacent pipe flanges remains, necessitating a more complex and time consuming procedure of having to support the pipe sections on jacks or cradles remains. This added timely repair procedure becomes costly as entire sections of a tank farm have to be shut down, thus affecting productivity.
Therefore a need exists for a butterfly valve assembly for inline placement in above-ground pipelines which is capable of quick change-out for repair or replacement, which reduces down-time to the minimal amount necessary.
The foregoing reflects the state of the art of which the inventor is aware, and is tendered with a view toward discharging the inventor's acknowledged duty of candor, which may be pertinent to the patentability of the present invention. It is respectfully stipulated, however, that the foregoing discussion does not teach or render obvious, singly or when considered in combination, the inventor's claimed invention.